1. Field of the Invention
The present invention generally relates to a rotary type developing device. More specifically, the present invention relates to a rotary type developing device for developing color images.
2. Background Information
Image forming apparatuses capable of forming color images are provided with a plurality of color developing devices each of which internally contains a developer for a respectively different color. There are image forming apparatuses that are provided with rotary developing devices installed on a single frame that allows the plurality of developing devices to rotate as seen in Japanese Laid-Open Patent Publication No. 2005-24575.
When forming a color image in an image forming apparatus provided with rotary type developing devices, the rotary developing devices are rotated and each developing device is sequentially moved to a developing position to develop a respective color. In rotary developing devices of this type, the frame is provided with annular gear members on bilateral ends of the frame in the direction of the axis of rotation. A motor and gear for driving the gear members are arranged in the image forming apparatus. The annular gear member is formed of resin. Therefore, the base and the gear teeth of the rotary developing device come into direct contact when the rotary developing device is being assembled or undergoing maintenance, which may lead to the gear teeth being damaged. When the gear teeth have been damaged, the gear teeth engage poorly and the developing position is shifted out of position. Further, when the developing position is shifted, image quality is reduced.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved a rotary type developing device for developing color images. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.